I have noticed the B618 on Ethernet Wan doesn't perform so well.
You using Ethernet and not wifi right?
WIFI currently but it doesn't seem to make a difference. Here is on ethernet:

When I reset the router:

Not 500/250 but much better. Strange that it seems to just be the DL speed affected here.
EDIT: performed a few more tests all around the same as the last. Seems that 200Mbps is the max it can hit.



